By citing your sources, you're showing your reader where you got your information.
It is important to distinguish the sources of information that you use from your own
ideas, interpretations, and conclusions. Failure to cite your sources is plagiarism.

Zotero

Library Extension

Install this free extension for Chrome (Firefox coming soon) that automatically shows
you whether the library has a book when you search sites like Amazon - that way you
never buy a book the library owns!